形状记忆合金驱动器的力学性能

基于形状记忆合金（ＳＭＡ）材料的Ｂｒｉｎｓｏｎ本构关系，研究了ＳＭＡ驱动器在自由冷却和强制冷却等两种热交换形式下的动力响应问题，探讨了ＳＭＡ丝在恒载及荷载变化时完成正逆相变所需用的时间．研究结果表明，热交换方式对完成相变时间有较大影响，并且增加散热面积和提高热交换速率均可有效地加速相变的完成．最后，本文还简单讨论了影响ＳＭＡ驱动器响应时间的几个因素和改进方法．

Mechanical behavior of shape memory alloy actuator

In this paper,the constitutive relation of SMA material proposed by Brinson is adopted in the study of dynamic response of SMA actuator under two types of heat transferring models: resistive heating with free convection cooling and forced convection cooling. At the same time, the loading influences on the period of completing transformation are analyzed. The results show that heat transferring types will exert larger influence on the period of completing transformation. The method of increasing the structural surface to enhance the heat transfer rate is very effective and yet limited by structure design. Those factors and methods forimprovement that influence actuator's response are discussed in brief.